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Types vs Interfaces

interface vs type

[!Rule of thumb: which to use: interface vs type]- use types unless you need a specific feature of interfaces

[!Why?]- interface: declaration merging if you redefine an interface somewhere else, it just extends it causes a bug

Interface vs type: not gonna be the TypeScript compiler bottleneck

[!What only interface can do]- - declaration merging - interfaces can be changed after being created

interface Point {
    x: number;
interface Point {
    y: number;
//becomes: interface Point { x: number; y: number; }

[!What only type can do]- - primitives - type Name = string - unions - type Id = string | number - tuples - type Data = [number, string]

Last update: 2023-04-24